Hi FolksFew weeks back I had my car at an indy shop for CEL stuff and they replaced my MAF sensor (first time that had been done).

I've noticed a few times after this an issue (never before experienced) with a rough idle (every few seconds it would be blipping up to 800rpm then back down to 600, repeat, repeat)

Was in dealer for separate issue today and had asked them to check this. They couldn't duplicate the issue but asked me to check, especially if MAF sensor was recently replaced, that the correct MAF part# was used (said there were 3 different part#'s made and if you put the wrong one on you could have issues with that).

Just read thru my "101 Projects for your Porsche Boxster" book (p.109 in the MAF replace project) - from what I read, for my car, that part# the indy used is the latest/greatest one but they also state something about "Porsche updated the sensors in the Boxster in mid-2000 and also released a new version of the DME software that is a required updated if you are going to use this new and improved sensor (see Porsche Tech Bulletin Boxster 1a/00 2445)"

So....maybe the indy didn't update the DME software? (it wasn't stated anywhere on my receipt and I know they didn't mention it to me that they were doing it at the time they did this MAF replacement)

Is it safe to assume any decent indy shop would have access to these Porsche tech bulletins? Or is that only available thru a Porsche dealership?

You may want to make 100% sure you have the correct MAF. They all look pretty much the same but their sensor characteristics have to be matched to you particular car. The 2000 year is a cross over year.

I had a new MAF put into my 2000 Boxster S and they had to update the software with it. It was what they did back then.... IIRC, they didn;t "select" the correct MAF, they just used up the old inventory, and then moved to the new MAF with software. I am a bit surprised they even make the older part.

However, you dipping and bobbing RPMs may be as simple as cleaning your throttle body. Very easy to do.... take of the hoses and just spray cleaner in and around the butterfly.... jam a small rag in there with a screwdriver and you will pull out jet black oil stuff. I put 197K miles on my 2000 S and cleaning the throttle body to stop the bobbing was a common routine for me.... I can't remember how often or whatever, but I just began to do it as a standard maintenance procedure after the dealer did the clean (and charged me!).

Thanks BruceYeah I saw some video of some instructions for cleaning the throttle body. Little hesitant to try it as I've never worked on the engine other than oil/filter changes. But the video sure may it seem feasible....so far my rough idle is only happening sporadically.

I spoke to my Porsche dealer yesterday on this - he told me that on these older cars they usually wouldn't even update the software/ECM after putting in a new MAF. Supposedly it's likely to fry the ECM and cost me a new ECM. So he said try to live with it if you are worried about the ECM chgs not having been made after replacing your MAF (like on mine).

Just make sure to get the proper cleaner. Make sure the rag you use does not leave parts behind. Cover your top and window and exposed paint to protect against overspray if you are going to clean in situ.

If you remove the whole component, it is easier to clean, but there are obviously more steps.You will be fine.